If standby_file_management set to manual

if standby_file_management set to manual and file got created on prod and not in DR then it will fail with below  error:
Errors in file /orabin/oracle/admin/ABCPRD/diag/diag/rdbms/abcprd_drabcdbstd03/ABCPRD/trace/ABCPRD_mrp0_21744.trc:
ORA-01111: name for data file 11 is unknown - rename to correct file
ORA-01110: data file 11: '/orabin/oracle/product/11g/dbs/UNNAMED00011'
ORA-01157: cannot identify/lock data file 11 - see DBWR trace file
ORA-01111: name for data file 11 is unknown - rename to correct file
ORA-01110: data file 11: '/orabin/oracle/product/11g/dbs/UNNAMED00011'

To fix this kind of issue:

SQL> alter database create datafile '/orabin/oracle/product/11g/dbs/UNNAMED00011' as '/oradata/ABCPRD/sysaux05.dbf';

Database altered.

SQL> alter database mount standby database;

SQL>
SQL> alter database recover managed standby database disconnect from session;

Database altered.

SQL> !ps -ef |grep mrp
oracle   22988     1  4 18:50 ?        00:00:00 ora_mrp0_ABCPRD
oracle   23012 22894  0 18:50 pts/3    00:00:00 /bin/bash -c ps -ef |grep mrp
oracle   23014 23012  0 18:50 pts/3    00:00:00 grep mrp